Want to schmooze with the next big innovator? Forget high-priced conferences. Head to an 'unconference' instead, writes Business 2.0's Chris Taylor.

(Business 2.0 Magazine) -- It was a match made in geek heaven: Steve Jobs and Bill Gates together on the same stage for the first time in twenty years. And the audience, 500 of them, had paid $4,000 for the privilege of seeing it all.

Silicon Valley is still buzzing about the matchup at D: All Things Digital, the annual tech conference run by the Wall Street Journal's Kara Swisher and Walt Mossberg. The four-year-old confab is a relatively new entry in an exploding market of elite, invitation-only and highly profitable conferences such as TED (for Technology, Entertainment and Design) and Web 2.0. Supernova, another new $2,000-a-head conference, is set to open in a couple of weeks.

D: All Things Digital attendees paid a hefty fee to see Steve Jobs and Bill Gates take a walk down memory lane last week. But was the confab worth the price?

Not long after the crowd of old, rich tech hands schmoozed and reminisced at D, the next generation of geeks, from companies like Adobe (Charts), Intel (Charts, Fortune 500) and Yahoo (Charts, Fortune 500), got way more interactive at the Online Community Unconference in Mountain View.

There was no agenda, but in a single day, participants created and ran more than 40 sessions. At one called "Speed Geeking," you could see ten products, websites and ideas demonstrated every hour. The cost? Less than $200 a head.

Even as big-ticket D-style conferences have proliferated, so too have "unconferences." Just as programmers are using what they call "open source" to collaboratively build free software like Linux, unconference organizers are using what they call "open space" principles to build low-cost, design-it-yourself confabs.

At Silicon Valley gatherings like Bar Camp, it is your ideas, not your celebrity, that matter; at Mashup Camp, held in July, it is how well you put ideas together.

Call them gatherings for the Internet age. "We can read or see the presentations online beforehand," says Kaliya Hamlin, a veteran unconference organizer. "So what is the point of just watching talking heads?"

It is on the growing circuit of unconferences that you would go if you wanted to meet the Jobs and Gates of tomorrow. The founders of Apple (Charts, Fortune 500) and Microsoft (Charts, Fortune 500) would never have been able to afford D or TED while they were working on Basic or the Apple II.

When Jobs and Apple co-founder Wozniak were penniless students haunting garages, and they wanted to confab with their smartest Silicon Valley cohorts, they went to the 1970s progenitor of the unconference, the now-legendary Homebrew Computer Club. Gates, a college dropout writing code for a kit computer, also crossed paths with this crowd.

The big-ticket conferences, of course, have networking to die for. TED is the elite of the elite. At TED's annual 1,000-person get-together in the seaside city of Monterey, Calif., speaker-attendees have included Jeff Bezos, Bill Clinton, Dean Kamen, uber-VC John Doerr, Malcolm Gladwell, Bono, Al Gore, and the Google guys -- not to mention the finest scientists and designers.

Despite the ticket price rising to $6,000, TED is already sold out for next February. Attendees of a spin-off event called TED Global have just wrapped up the event in Tanzania and are now embarking on exclusive safaris and climbing expeditions to Mount Kilimanjaro. Inspirational, perhaps, but hardly a venue to write and create new products.

TED and the unconferences both provide smart people with an opportunity to meet like-minded people. But the dirty little secret of unconferences is that you don't have to spend thousands of dollars to get good networking. You just have to name the meeting place.

Often, this is right next to the big-ticket conference itself -- as in the case of Supernova, the upcoming San Francisco event that attracts the likes of Sergey Brin and Esther Dyson. As Supernova takes place later this month, a free unconference, organized by Hamlin, will be going on right next door.

One will have plenty of panels, the other plenty of hungry entrepreneurs. Which would you rather go to?

"Unconferences are peer-to-peer learning," says Hamlin. "Invitation is the most important element: Why do you want people to come together, and what do you want to talk about? People who share a passion create the day."

If Gates and Jobs had sat down and mashed up some ideas, rather than simply reminisce at the behest of interviewers, who knows what they could have created.

Chris Taylor, a senior editor at Business 2.0 Magazine, blogs about the next big business opportunity.